Web design conference - CHAPTER 29 INSTALLING SOFTWARE Backports: A Backports
CHAPTER 29 INSTALLING SOFTWARE Backports: A Backports server allows access to software that s intended to go into the next version of Ubuntu but which has been packaged for the current version. This software might not have been tested thoroughly and so is suitable for neophiliacs or those who absolutely need the latest version (perhaps because of a vital new feature it offers). Security Updates: Although the Updates server supplies newer versions of the main Ubuntu packages, sometimes security flaws need to be fixed almost immediately. If so, the packages concerned will be placed on this server. The Security Updates server isn t about new versions or functionality. It s about fixing security holes. Note Sometimes, you might choose to add an additional repository. For example, in Chapter 28, you added the official Wine repository so you could install the latest version of the software that lets you run Windows programs. Repository Sections In addition to the categories listed in the previous sections, the Ubuntu repositories are split into sections according to how essential the software is to a basic Ubuntu installation, or the license that the software uses. Here are the sections under which software is filed within a repository: Main: This section contains nearly all the software that s featured in a basic Ubuntu installation. As such, it s all Free Software, and every package is supported by the Ubuntu project. That means that updates are frequently provided to fix security holes, or simply to keep up with latest releases. Note Free Software refers to software that s licensed under the GNU Public License (GPL). It doesn t mean that the software is free of charge, although that s nearly always the case. Restricted: Although Ubuntu is mostly Free Software, it must include some components that have license agreements that are not compatible with the goals of Free Software. That s what you ll find in this section. Many Ubuntu installations simply won t work fully without software from the Restricted section. The chief examples are hardware drivers that are released only in binary form (that is, closed source). Universe: This section might be referred to as the rest, because it contains the majority of Free Software available at the present time. Much of it is raided from the massive Debian software library, although the packages are sometimes tweaked to work correctly under Ubuntu before being made available. Unlike Main and Restricted, the Universe section is not officially supported by the Ubuntu project, which means there s no guarantee that security flaws will be fixed. Nor is there any guarantee of updates.